| 引用本文: | 马己安,冯克鹏,李王成,等.基于水面蒸发量的宁夏中部干旱带土壤蒸发量估算研究[J].灌溉排水学报,2020,39(10):35-41. |
| ,et al.基于水面蒸发量的宁夏中部干旱带土壤蒸发量估算研究[J].灌溉排水学报,2020,39(10):35-41. |
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| 摘要: |
| 【目的】分段拟合宁夏中部干旱地区基于水面蒸发量和含水率的土壤蒸发量计算经验公式。【方法】采用室外土柱试验，通过分析压砂地和裸地土壤蒸发量与水面蒸发量之间的关系，依据土壤蒸发量（Eb）与水面蒸发量（E0）的比值随时间和含水率（Q）的变化趋势划分当地土壤蒸发各个阶段。【结果】根据试验数据可将裸地蒸发过程分为3个阶段，将压砂地蒸发过程分为2个阶段。裸地蒸发过程3个阶段存在2个临界值，分别为0.209 6 g/g＜θb1＜0.214 8 g/g和0.114 0 g/g＜θb2＜0.115 4 g/g，压砂地蒸发过程2个阶段存在1个临界值为0.208 1 g/g＜θg＜0.214 7 g/g。依据以上含水率临界值将压砂地和裸地土壤蒸发和水面蒸发之间的关系分段建立了经验公式。【结论】根据水面蒸发量和土壤含水率推求土壤蒸发量，精度较高，可为当地水资源管理提供参考依据。 |
| 关键词: 压砂地；土壤含水率；土壤蒸发；水面蒸发 |
| DOI：10.13522/j.cnki.ggps.2019466 |
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| Using Water Surface Evaporation to Estimate Soil Surface Evaporation in Arid Regions in Central Ningxia |
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MA Ji’an, FENG Kepeng, LI Wangcheng, HAO Lu, LI Yukun, GAO Haiyan
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1. School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, China; 2.Engineering Technology Research Center of Water-saving and Water Resource Regulation in Ningxia, Yinchuan 750021, China; 3. Engineering Research Center of Efficient Utilization of Modern Agricultural Water Resources in Arid Regions, Ministry of Education, Yinchuan 750021, China
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| Abstract: |
| 【Background】The arid regions in central Ningxia are characterized by scarce precipitation and high evaporation, with meteorological data from 1960 to 2016 showing an average annual precipitation of 183.1 mm compared to 2 000 mm of evaporation. Water-saving irrigation has been substantially improved in these regions, but water shortage is still the bottleneck restricting their agricultural production. Mulching the lands with gravels is a main cultivation method in these regions, and it is thus important to understand how the mulch alters the evaporation compared to that from bare soil, as soil evaporation is an important component in hydrological cycling and its calculation is not trivial and varies with disciplines.【Objective】 This paper aims to elucidate the relationship between soil surface evaporation and water surface evaporation, as well as the impact of soil water content in bare soil and the gravel-mulched soil on this relationship.【Method】 Outdoor experiments were conducted to analyze the relationship between soil surface evaporation and water surface evaporation using columns packed with both gravel-mulched soil and bare soil respectively. Soil evaporation was divided into different stages based on the ratio of soil surface evaporation to water surface evaporation at different times and water contents, and an empirical formula was derived to describe their relationships.【Result】 Evaporation from the bare soil could be divided into three stages while that from the gravel-mulched soil into two. The two critical ratios distinguishing the three evaporation stages in the bare soil were 0.209 6 g/g<θb1<0.214 8 g/g and 0.114 0 g/g<θb2<0.115 4 g/g respectively, while for evaporation from the gravel-mulched soil the critical ratio was 0.208 1 g/g<θg<0.214 7 g/g.【Conclusion】 The empirical formula derived based on the critical ratio was accurate to estimate soil surface evaporation from both the bare soil and the gravel-mulched soil. It can be used in agricultural water management and water resources planning to help design water-saving irrigation technologies and offer an alternative to study soil evaporation in these regions. |
| Key words: gravel-mulch; soil moisture; soil evaporation; water surface evaporation |
